package org.mp4parser.muxer;
import org.mp4parser.Box;
import org.mp4parser.Container;
import org.mp4parser.boxes.iso14496.part12.*;
import org.mp4parser.boxes.iso23001.part7.CencSampleAuxiliaryDataFormat;
import org.mp4parser.boxes.iso23001.part7.TrackEncryptionBox;
import org.mp4parser.muxer.tracks.CencEncryptedTrack;
import org.mp4parser.tools.IsoTypeReader;
import org.mp4parser.tools.Path;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.UUID;
/**
* This track implementation is to be used when MP4 track is CENC encrypted.
*/
public class CencMp4TrackImplImpl extends Mp4TrackImpl implements CencEncryptedTrack {
private List<CencSampleAuxiliaryDataFormat> sampleEncryptionEntries;
private UUID defaultKeyId;
/**
* Creates a track from a TrackBox and potentially fragments. Use <b>fragements parameter
* only</b> to supply additional fragments that are not located in the main file.
*
* @param trackId ID of the track to extract
* @param isofile the parsed MP4 file
* @param randomAccess the RandomAccessSource to read the samples from
* @param name an arbitrary naem to identify track later - e.g. filename
* @throws java.io.IOException if reading from underlying <code>DataSource</code> fails
*/
public CencMp4TrackImplImpl(final long trackId, Container isofile, RandomAccessSource randomAccess, String name) throws IOException {
super(trackId, isofile, randomAccess, name);
TrackBox trackBox = null;
for (TrackBox box : Path.<TrackBox>getPaths(isofile, "moov/trak")) {
if (box.getTrackHeaderBox().getTrackId() == trackId) {
trackBox = box;
break;
}
}
SchemeTypeBox schm = Path.getPath(trackBox, "mdia[0]/minf[0]/stbl[0]/stsd[0]/enc.[0]/sinf[0]/schm[0]");
assert schm != null && (schm.getSchemeType().equals("cenc") || schm.getSchemeType().equals("cbc1")) : "Track must be CENC (cenc or cbc1) encrypted";
sampleEncryptionEntries = new ArrayList<CencSampleAuxiliaryDataFormat>();
final List<MovieExtendsBox> movieExtendsBoxes = Path.getPaths(isofile, "moov/mvex");
if (!movieExtendsBoxes.isEmpty()) {
for (MovieFragmentBox movieFragmentBox : isofile.getBoxes(MovieFragmentBox.class)) {
List<TrackFragmentBox> trafs = movieFragmentBox.getBoxes(TrackFragmentBox.class);
for (TrackFragmentBox traf : trafs) {
if (traf.getTrackFragmentHeaderBox().getTrackId() == trackId) {
TrackEncryptionBox tenc = Path.getPath(trackBox, "mdia[0]/minf[0]/stbl[0]/stsd[0]/enc.[0]/sinf[0]/schi[0]/tenc[0]");
assert tenc != null;
defaultKeyId = tenc.getDefault_KID();
long baseOffset;
if (traf.getTrackFragmentHeaderBox().hasBaseDataOffset()) {
baseOffset = traf.getTrackFragmentHeaderBox().getBaseDataOffset();
} else {
Iterator<Box> it = isofile.getBoxes().iterator();
baseOffset = 0;
for (Box b = it.next(); b != movieFragmentBox; b = it.next()) {
baseOffset += b.getSize();
}
}
FindSaioSaizPair saizSaioPair = new FindSaioSaizPair(traf).invoke();
SampleAuxiliaryInformationOffsetsBox saio = saizSaioPair.getSaio();
SampleAuxiliaryInformationSizesBox saiz = saizSaioPair.getSaiz();
// now we have the correct saio/saiz combo!
assert saio != null;
long[] saioOffsets = saio.getOffsets();
assert saioOffsets.length == traf.getBoxes(TrackRunBox.class).size();
assert saiz != null;
List<TrackRunBox> truns = traf.getBoxes(TrackRunBox.class);
int sampleNo = 0;
for (int i = 0; i < saioOffsets.length; i++) {
int numSamples = truns.get(i).getEntries().size();
long offset = saioOffsets[i];
long length = 0;
for (int j = sampleNo; j < sampleNo + numSamples; j++) {
length += saiz.getSize(j);
}
ByteBuffer trunsCencSampleAuxData = randomAccess.get(baseOffset + offset, length);
for (int j = sampleNo; j < sampleNo + numSamples; j++) {
int auxInfoSize = saiz.getSize(j);
sampleEncryptionEntries.add(
parseCencAuxDataFormat(tenc.getDefaultIvSize(), trunsCencSampleAuxData, auxInfoSize)
);
}
sampleNo += numSamples;
}
}
}
}
} else {
TrackEncryptionBox tenc = Path.getPath(trackBox, "mdia[0]/minf[0]/stbl[0]/stsd[0]/enc.[0]/sinf[0]/schi[0]/tenc[0]");
assert tenc != null;
defaultKeyId = tenc.getDefault_KID();
ChunkOffsetBox chunkOffsetBox = Path.getPath(trackBox, "mdia[0]/minf[0]/stbl[0]/stco[0]");
if (chunkOffsetBox == null) {
chunkOffsetBox = Path.getPath(trackBox, "mdia[0]/minf[0]/stbl[0]/co64[0]");
}
assert trackBox != null;
assert chunkOffsetBox != null;
long[] chunkSizes = trackBox.getSampleTableBox().getSampleToChunkBox().blowup(chunkOffsetBox.getChunkOffsets().length);
FindSaioSaizPair saizSaioPair = new FindSaioSaizPair((Container) Path.getPath(trackBox, "mdia[0]/minf[0]/stbl[0]")).invoke();
SampleAuxiliaryInformationOffsetsBox saio = saizSaioPair.saio;
SampleAuxiliaryInformationSizesBox saiz = saizSaioPair.saiz;
if (saio.getOffsets().length == 1) {
long offset = saio.getOffsets()[0];
int sizeInTotal = 0;
if (saiz.getDefaultSampleInfoSize() > 0) {
sizeInTotal += saiz.getSampleCount() * saiz.getDefaultSampleInfoSize();
} else {
for (int i = 0; i < saiz.getSampleCount(); i++) {
sizeInTotal += saiz.getSampleInfoSizes()[i];
}
}
ByteBuffer chunksCencSampleAuxData = randomAccess.get(offset, sizeInTotal);
for (int i = 0; i < saiz.getSampleCount(); i++) {
sampleEncryptionEntries.add(
parseCencAuxDataFormat(tenc.getDefaultIvSize(), chunksCencSampleAuxData, saiz.getSize(i))
);
}
} else if (saio.getOffsets().length == chunkSizes.length) {
int currentSampleNo = 0;
for (int i = 0; i < chunkSizes.length; i++) {
long offset = saio.getOffsets()[i];
long size = 0;
if (saiz.getDefaultSampleInfoSize() > 0) {
size += saiz.getSampleCount() * chunkSizes[i];
} else {
for (int j = 0; j < chunkSizes[i]; j++) {
size += saiz.getSize(currentSampleNo + j);
}
}
ByteBuffer chunksCencSampleAuxData = randomAccess.get(offset, size);
for (int j = 0; j < chunkSizes[i]; j++) {
long auxInfoSize = saiz.getSize(currentSampleNo + j);
sampleEncryptionEntries.add(
// should I use the iv size from the sample group?
parseCencAuxDataFormat(tenc.getDefaultIvSize(), chunksCencSampleAuxData, auxInfoSize)
);
}
currentSampleNo += chunkSizes[i];
}
} else {
throw new RuntimeException("Number of saio offsets must be either 1 or number of chunks");
}
}
}
private CencSampleAuxiliaryDataFormat parseCencAuxDataFormat(int ivSize, ByteBuffer chunksCencSampleAuxData, long auxInfoSize) {
CencSampleAuxiliaryDataFormat cadf = new CencSampleAuxiliaryDataFormat();
if (auxInfoSize > 0) {
cadf.iv = new byte[ivSize];
chunksCencSampleAuxData.get(cadf.iv);
if (auxInfoSize > ivSize) {
int numOfPairs = IsoTypeReader.readUInt16(chunksCencSampleAuxData);
cadf.pairs = new CencSampleAuxiliaryDataFormat.Pair[numOfPairs];
for (int i = 0; i < cadf.pairs.length; i++) {
cadf.pairs[i] = cadf.createPair(
IsoTypeReader.readUInt16(chunksCencSampleAuxData),
IsoTypeReader.readUInt32(chunksCencSampleAuxData));
}
}
}
return cadf;
}
public UUID getDefaultKeyId() {
return defaultKeyId;
}
public boolean hasSubSampleEncryption() {
return false;
}
public List<CencSampleAuxiliaryDataFormat> getSampleEncryptionEntries() {
return sampleEncryptionEntries;
}
@Override
public String toString() {
return "CencMp4TrackImpl{" +
"handler='" + getHandler() + '\'' +
'}';
}
@Override
public String getName() {
return "enc(" + super.getName() + ")";
}
private class FindSaioSaizPair {
private Container container;
private SampleAuxiliaryInformationSizesBox saiz;
private SampleAuxiliaryInformationOffsetsBox saio;
public FindSaioSaizPair(Container container) {
this.container = container;
}
public SampleAuxiliaryInformationSizesBox getSaiz() {
return saiz;
}
public SampleAuxiliaryInformationOffsetsBox getSaio() {
return saio;
}
public FindSaioSaizPair invoke() {
List<SampleAuxiliaryInformationSizesBox> saizs = container.getBoxes(SampleAuxiliaryInformationSizesBox.class);
List<SampleAuxiliaryInformationOffsetsBox> saios = container.getBoxes(SampleAuxiliaryInformationOffsetsBox.class);
assert saizs.size() == saios.size();
saiz = null;
saio = null;
for (int i = 0; i < saizs.size(); i++) {
if (saiz == null && (saizs.get(i).getAuxInfoType() == null) || "cenc".equals(saizs.get(i).getAuxInfoType())) {
saiz = saizs.get(i);
} else if (saiz != null && saiz.getAuxInfoType() == null && "cenc".equals(saizs.get(i).getAuxInfoType())) {
saiz = saizs.get(i);
} else {
throw new RuntimeException("Are there two cenc labeled saiz?");
}
if (saio == null && (saios.get(i).getAuxInfoType() == null) || "cenc".equals(saios.get(i).getAuxInfoType())) {
saio = saios.get(i);
} else if (saio != null && saio.getAuxInfoType() == null && "cenc".equals(saios.get(i).getAuxInfoType())) {
saio = saios.get(i);
} else {
throw new RuntimeException("Are there two cenc labeled saio?");
}
}
return this;
}
}
}